This has been bugging me! Radial tires does direction matter??

[zzvyb6]

Tires are designed and manufactured to be round. Roads are generally flat. The round tire on a flat road requires a portion the tire tread to slip in order to roll along the road. This slippage occurs at the rear portion of the tread as it departs the roadway. This slippage (or scrub) is responsible for a good portion of the tires rolling resistance (which vehicle manufacturers are all trying to minimize for fuel economy reasons). The tread scrubbing tends to produce a saw-tooth appearing wear called "heel-toe". No, its not the same as wear from "toe angle" alignment issues.

When you reverse the rotation directions, the first thing you will notice is a large increase in tread noise because now the angular worn tread blocks (as seen from the side view) are hitting the roadway backwards from their former orientations. They will eventually grind back down to a block more worn in the front, but the process will be accelerated because there is more pressure on the saw teeth tips that the tread floor is sitting on. Large forces on the tread from driveline (acceleration or braking) and even from heavy cornering also can produce heel/toe wear patterns in the direction the forces are pointed.

You should be able to produce an educated guess for what this means in terms of wear, traction, rolling resistance, noise, and longevity. I was a tire engineer for many a year, but I'd rather not hear any comments from those unfamiliar with combined tire engineering, manufacturing and testing processes. I'm retired now and don't wish to have "return to work" nightmares!

Yes, I rotate the tires on my truck and cars.

Go figure.

 

[Texasmark]

My 2011 Silverado came with non-directional radials as the standard tire. The owners manual shows that you can either go straight front to rear to keep tire rolling in the same direction like we had to do when radials first became available here, or you can cris-cross like we did with bias ply tires.

My understanding that the problems that plagued us initially have been worked out.

With the tire fiasco that Ford went through with Firestone not too many years ago I seriously doubt that an OEM truck mfgr. would specify crossing if not justifiable.

Mark

 

[bcp]

Your choice; straight, diagonal, or according to vehicle mfg, unless they are directional tires.

Cooper:
Object moved

Michelin;
Tire Rotation | Michelin Tires

Firestone:
http://www.firestonecompleteautocare.com/catalog/full-warranty.pdf

Bridgestone:
http://www.bridgestonetire.com/content/dam/bst/pdf/tire-warranties/GM_OE_Warranty_EN.pdf

Goodyear truck:
http://www.goodyeartrucktires.com/pdf/resources/publications/2010 RV Care and Maintenance Guide.pdf

Tire rack:
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=43

 

[Complete Turf Care]

I know this is an old thread, but I just rotated the tires on my Dodge 3500 dually today.

We put the left front to the inside left rear, and the inside left rear to the to the outside left rear and the outside left rear to the left front. This way, only the inside left rear (which was the left front) is now turning in the same direction as before the rotation. We did the same rotation on the right.

The front tires were showing the most wear. The truck has 13,000 miles on it and this is the first rotation.

Based on the comments earlier in this thread from a former tire engineer, this was probably as good a way to rotate as any, without dismounting any tires.

The young man at the tire shop didn't seem to know which way was best to rotate on a dually. He said people do it different ways.

 

[ch1ch2]

I know they say it does not matter. Maybe it doesn't. I know that in the 80's I rotated my tires in an x pattern and all four tires came apart within 6 months.
I will never do it again.

 

[Mikeeemo]

Crossing tires is to remove wear patterns in the tread. This occurs the most on steering axles. Moving to drive axles and turning the other direction helps remove the pattern.

As far a separation of the tread; if it occurs it is going to occur regardless.

For tire rotation to be beneficial, it needs to be done frequently.

 

[RalphVa]

This question is about automotive and class eight highway truck tires.

I have heard this myth time and time again from the older generation. They tell me once a radial tire has started being turned in one direction then, you do not change the direction of rotation. It is said when you change the direction of the tire it will wear out excessively fast and twist the belts in the tire. I have seen directional and non directional tires and non directional tires. I mostly work with tractor trailer and trailer tires but I have seen a few automotive tires that are directional.

Some people and car owners manuals say to rotate tires front and back some say to cross them. At my job at a truck shop (class eight tandem drive axle trucks) they want us to start crossing the tires on the drive axle. So left front will go onto right rear and right rear duals onto left front and so on. Some mechanics say the tires on these trucks (295/75/22.5) will wear out fast after the direction is changed. What do you think?

I've rotated to opposite side before. Now, our new Mazda calls for exactly that: right rear to left front, back to left rear, over to right front and back to right rear. That's the way I've done it before. With floor jacks, one needs to use a 5th "dummy" wheel on the right rear and then remove it as the right front gets moved back. That's the way I did it and will do it using the temp spare on the Mazda.

Ralph

 

[Garandman]

I used to sell tires.

The crossing of tires is to counteract negative wear patterns that develop in the steer axle tires, in some situations. The part about not crossing started over the first generation radial tires, and has stuck ever since. These tires had problems. //

Specifically, the steel belts. I'm not sure steel belt radials are even made anymore. (Update, yes, a few).

 

[PILOON]

I always figured that the cost of having them rotated ($40.00) cancelled out the added mileage I might gain.
Besides, here in Quebec we have a law that mandates snow tires on all 4 wheels from Oct to May so that makes for a rotation as long as you mark where they were. On our tires you always find a yellow code, like L F or RR, showing where they were installed.
Most of us have 2 sets of rims, mags for summer and steel with snows mounted.
All seasons are not accepted even on a 4 X 4.
Oddly enough buses and trucks are exempted from from this law.(gov't saving dollars)
We are subjected to fines if caught but a special permit is available for those that travel south for the winter. Permit is valid for a 7 day window.
On the other hand the only time a fine is levied is if you are involved in an accident as we, so far, don't have tire police.

 

[Complete Turf Care]

I always figured that the cost of having them rotated ($40.00) cancelled out the added mileage I might gain.

My cost to rotate was $16.50 including 10% sales tax. And that's on a dually.

My uneducated guess is that I get an extra 40% life out of my tires if I rotate about every 10,000 miles, or 50,000 miles instead of 30,000.